Kenwood Brandon M, Bagchi Pritha, Zhang Luyu, Zhu Wanzhe, Chambers David M, Blount Benjamin C, De Jesús Víctor R
Tobacco and Volatiles Branch, Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA, 30341, USA.
Emory Integrated Proteomics Core, Emory University, Atlanta, GA, 30322, USA.
Environ Sci Pollut Res Int. 2021 Apr;28(13):16781-16791. doi: 10.1007/s11356-020-12135-7. Epub 2021 Jan 4.
Methylcarbamoyl mercapturic acid (MCAMA, N-acetyl-S-(N-methylcarbamoyl)-L-cysteine) is a urinary metabolite of N,N-dimethylformamide and methyl isocyanate, which are volatile organic compounds that are harmful to humans. N,N-dimethylformamide exposure causes liver damage, and methyl isocyanate inhalation damages the lining of the respiratory tract, which can increase risk of chronic obstructive pulmonary disease and asthma. This study characterizes urinary MCAMA levels in the US population and explores associations of MCAMA concentrations with select demographic and environmental factors. We used liquid chromatography tandem mass spectrometry to measure MCAMA in urine collected from study participants ≥ 12 years old (N = 8272) as part of the National Health and Nutrition Examination Survey 2005-2006 and 2011-2016. We produced multiple regression models with MCAMA concentrations as the dependent variable and sex, age, fasting time, race/ethnicity, diet, and cigarette smoking as independent variables. Cigarette smokers and nonsmokers had median urinary MCAMA concentrations of 517 μg/g creatinine and 127 μg/g creatinine, respectively. Sample-weighted multiple regression analysis showed that MCAMA was positively associated with serum cotinine (p < 0.0001). Compared to non-exposed participants (serum cotinine ≤ 0.015 ng/mL), presumptive exposure to second-hand tobacco smoke (serum cotinine > 0.015-≤ 10 ng/mL and 0 cigarettes smoked per day) was associated with 20% higher MCAMA (p < 0.0001). Additionally, smoking 1-10 cigarettes per day was associated with 261% higher MCAMA (p < 0.0001), smoking 11-20 cigarettes per day was associated with 357% higher MCAMA (p < 0.0001), and smoking > 20 cigarettes per day was associated with 416% higher MCAMA (p < 0.0001). These findings underscore the strong association of tobacco smoke exposure with urinary MCAMA biomarker levels.
甲基氨基甲酰巯基尿酸（MCAMA，N-乙酰基-S-（N-甲基氨基甲酰基）-L-半胱氨酸）是N，N-二甲基甲酰胺和甲基异氰酸酯的尿液代谢产物，这两种挥发性有机化合物对人体有害。接触N，N-二甲基甲酰胺会导致肝脏损伤，吸入甲基异氰酸酯会损害呼吸道内壁，这会增加患慢性阻塞性肺疾病和哮喘的风险。本研究对美国人群尿液中的MCAMA水平进行了特征分析，并探讨了MCAMA浓度与特定人口统计学和环境因素之间的关联。作为2005 - 2006年和2011 - 2016年国家健康与营养检查调查的一部分，我们使用液相色谱串联质谱法测量了年龄≥12岁的研究参与者（N = 8272）尿液中的MCAMA。我们建立了以MCAMA浓度为因变量，性别、年龄、禁食时间、种族/民族、饮食和吸烟为自变量的多元回归模型。吸烟者和非吸烟者尿液中MCAMA的中位数浓度分别为517μg/g肌酐和127μg/g肌酐。样本加权多元回归分析表明，MCAMA与血清可替宁呈正相关（p < 0.0001）。与未接触者（血清可替宁≤0.015 ng/mL）相比，推定接触二手烟草烟雾（血清可替宁> 0.015 -≤10 ng/mL且每天吸烟0支）与MCAMA升高20%相关（p < 0.0001）。此外，每天吸1 - 10支烟与MCAMA升高261%相关（p < 0.0001），每天吸11 - 20支烟与MCAMA升高357%相关（p < 0.0001），每天吸> 20支烟与MCAMA升高416%相关（p < 0.0001）。这些发现强调了烟草烟雾暴露与尿液中MCAMA生物标志物水平之间的密切关联。
